The present disclosure is related generally to the field of dental treatment. More particularly, the present disclosure is related to methods, systems, and devices for adjusting an arch of a patient.
Dental treatments may involve, for instance, restorative and/or orthodontic procedures. Restorative procedures may be designed to implant a dental prosthesis (e.g., a crown, bridge inlay, onlay, veneer, etc.) intraorally in a patient. Orthodontic procedures may include repositioning misaligned teeth and/or changing bite configurations for improved cosmetic appearance and/or dental function. Orthodontic repositioning can be accomplished, for example, by applying controlled forces to one or more teeth over a period of time.
As an example, orthodontic repositioning may be provided through a dental process that uses positioning appliances for realigning teeth. Such appliances may utilize a thin shell of material having resilient properties, referred to as an “aligner,” that generally conforms to a patient's teeth but is slightly out of alignment with a current tooth configuration.
Placement of such an appliance over the teeth may provide controlled forces in specific locations to gradually move the teeth into a new configuration. Repetition of this process with successive appliances in progressive configurations can move the teeth through a series of intermediate arrangements to a final desired arrangement.
Such systems typically utilize materials that are lightweight and/or transparent to provide a set of appliances that can be used serially such that as the teeth move, a new appliance can be implemented to further move the teeth toward the desired goal.
In some instances, the width of a dental arch of a patient's upper dentition and/or and a width of a dental arch of a patient's lower dentition can be insufficient (e.g., too narrow) and on rare occasions, the width may be excessive (e.g., Brodie bite). A dental arch that is insufficient can result in malocclusions such as crossbite, crowding of teeth, impacted teeth, and/or the patient's smile may not be aesthetically pleasing in appearance. For instance, a patient's smile may be “narrow”, resulting in a sunken appearance in the buccal corridors due to the inability to see the back teeth from the front view.
In certain types of front-to-back bite correction (e.g., Class II and Class III correction), a need for transverse width correction exists, without which the upper and lower arches will not be properly coordinated. For Class II correction, the upper needs to be expanded so that when the lower is advanced, the teeth in the buccal regions (typically the bicuspids and molars) are fitting together correctly in the buccal-lingual dimension. For Class III correction, the reverse is required, and the lower needs to be expanded since it is usually the one that has compensated for the Class III bite by constricting. When both Class II and Class III are corrected to a more ideal Class I bite, the respective compensations need to be undone, and a transverse width dimension of movement is necessary in addition to the anterior-to-posterior movement.
There are several ways in which the arch of a patient can be expanded. For example, palatal expansion expands the upper jaw of the patient by spreading the maxilla. In some situations, the teeth of the upper and/or lower jaw can be moved or angled outward thereby expanding the width of the arch of the patient. This technique can be referred to as dental expansion. Further, expansion of the lower arch in this manner is often referred to as mandibular expansion.
In young patients, the midpalatal suture has not fused the left and right maxillary palates together and therefore, the movement of the plates with respect to each other can be accomplished more easily and with less force than in older patients. When the fusing of the suture is new, it may still be possible to split the suture apart.
For example, currently available orthodontic appliances can include a jackscrew and/or other mechanism that is employed to deliver a horizontal stretching force to the molar teeth to split the upper jaw of the patient along the midpalatal suture. Such a mechanism typically spreads the left and right maxillary plates of the palate apart and then new bone material grows in between to fill the gap. As such, a large horizontal force (e.g., 10 to 50 Newtons (N) with cumulative loads reaching 40 to 150 N across the suture) is applied during a short period, in many cases. The insertion of such a mechanism is typically accomplished by a treatment professional and can cause discomfort and/or pain for a patient.
In some instances, the screw and/or other mechanism can be employed incrementally one or more times a day (e.g., 0.25 mm expansion twice a day—one activation in the morning and once at night). For example, a pinhole can be present in the orthodontic appliance and a patient can insert an activation key into the pinhole to incrementally increase a distance between portions of the orthodontic appliance.
Such orthodontic appliances can be difficult for a patient to use, and often require assistance from another person (e.g., a parent) to turn the key. Not only are such appliances often not aesthetically pleasing, they often times interfere with the patient's speech, temporarily affect their ability to chew and/or swallow, and/or can be painful when activated.
Adding to the challenges of such an appliance is the need to retain the expansion while the bone is filling into the suture, long after the active expansion has taken place. The active expansion process may be completed within 2 or 3 weeks' time, but the retention period can last around 6 months while waiting for the gap between the maxillary halves to fill in with new bony tissue.